LanguageFeatures/Spread-collections/DynamicSemantics_Set_A02_t01.dart

/*
 * Copyright (c) 2019, the Dart project authors.  Please see the AUTHORS file
 * for details. All rights reserved. Use of this source code is governed by a
 * BSD-style license that can be found in the LICENSE file.
 */
/**
 * @assertion A [set] literal [<E>{elem_1 ... elem_n}] is evaluated as follows:
 *   2. For each element in the [set] literal:
 *      i. Evaluate the element's expression to a value value.
 *      ii. If element is a spread element:
 *          a. If element is null-aware and value is [null], continue to the
 *             next element in the literal.
 *          b. Evaluate [value.iterator] to a [value] iterator.
 *          c. Loop:
 *             a. If [iterator.moveNext()] returns [false], exit the loop.
 *             b. Evaluate set.add(iterator.current).
 *       iii. Else:
 *           a. Evaluate [set.add(value)].
 * @description Checks that if element is null-aware and it's [null], nothing
 * added to the result set.
 * @author iarkh@unipro.ru
 */
// SharedOptions=--enable-experiment=constant-update-2018

import "../../Utils/expect.dart";

main() {
  List list1 = [100, 200, 300, 400, 500];
  List list2 = [];
  List list3 = null;
  List list4 = [1 ,2, 3, "checkme"];

  Expect.setEquals({}, {...?list3});
  Expect.setEquals({1, 2, 4}, {1, 2, ...?list3, 4});
  Expect.setEquals({10, 1, 2, 3, "checkme", 100, 200, 300, 400, 500},
      {10, ...?list4, ...?list3, ...list1});
  Expect.setEquals({}, {...?list3, ...?list3, ...?list3});
  Expect.setEquals({}, {...list2, ...?list3});
}